Bank segment (HEI only) - Securities Sold Under Agreements to Repurchase (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Securities sold under agreements to repurchase
Repurchase liability	$ 140,859	$ 92,618
Weighted-average interest rate	0.65%	0.23%
Collateralized by mortgage-related securities and federal agency obligations
Securities sold under agreements to repurchase
Collateralized by mortgage-related securities and federal agency obligations at fair value plus accrued interest	$ 165,464	$ 115,544
Overnight
Securities sold under agreements to repurchase
Repurchase liability	$ 140,859	$ 79,083
Weighted-average interest rate	0.65%	0.15%
Overnight \| Collateralized by mortgage-related securities and federal agency obligations
Securities sold under agreements to repurchase
Collateralized by mortgage-related securities and federal agency obligations at fair value plus accrued interest	$ 165,464	$ 100,305
1 to 29 days
Securities sold under agreements to repurchase
Repurchase liability	$ 0	$ 0
Weighted-average interest rate	0.00%	0.00%
1 to 29 days \| Collateralized by mortgage-related securities and federal agency obligations
Securities sold under agreements to repurchase
Collateralized by mortgage-related securities and federal agency obligations at fair value plus accrued interest	$ 0	$ 0
30 to 90 days
Securities sold under agreements to repurchase
Repurchase liability	$ 0	$ 13,535
Weighted-average interest rate	0.00%	0.70%
30 to 90 days \| Collateralized by mortgage-related securities and federal agency obligations
Securities sold under agreements to repurchase
Collateralized by mortgage-related securities and federal agency obligations at fair value plus accrued interest	$ 0	$ 15,239
Over 90 days
Securities sold under agreements to repurchase
Repurchase liability	$ 0	$ 0
Weighted-average interest rate	0.00%	0.00%
Over 90 days \| Collateralized by mortgage-related securities and federal agency obligations
Securities sold under agreements to repurchase
Collateralized by mortgage-related securities and federal agency obligations at fair value plus accrued interest	$ 0	$ 0

Assets Sold Under Agreements To Repurchase Fair Value Plus Accrued Interest

No definition available.

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- Definition

Interest rate on the amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(m)(1)(i)(A)(ii))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount to be repaid to the counterparty to the repurchase agreement when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under the repurchase agreement exceeds 10 percent of total assets.

+ References

+ Details

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